1. Aquarium Heaters Buying Guide
Aquarium Heaters Best Sellers
Tetra Submersible
Aquarium Heater,

Tetra Submersible
Aquarium Heater,

Hydro USA Mini
Aquarium Heater in

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How to choose an aquarium heater

how to choose aquarium heater

An aquarium heater buying guide

Aquarium heaters are often a necessary fish tank accessory for your fish tank. Additionally, these fish supplies are convenient because they can reduce the amount of time you need to spend cleaning the tank and changing the tank's water. What factors impact how to choose an aquarium heater that will work for your fish aquariums and bowls? All that you need to do is to consider a few simple points when it comes to aquarium heaters and coolers to find the best one to meet your needs.

>> What kind of aquarium heater do you want?

top rated aquarium heaters

There are four types of aquarium heaters that you should consider when thinking about how to choose an aquarium heater for your tank. These types of aquarium heaters include glass immersion heaters, undergravel heaters, under tank heaters and filter heaters.

  • Glass immersion heaters are glass tubes consisting of a heating element and a thermometer. The heating element kicks in when the thermometer detects that the water is too cold. Sometimes these glass tubes come encased in ceramic or are filled with sand to prevent the tubes from breaking. Glass immersion heaters are either fully submersible or partially submersible, and they often hang from the back of your tank. These types of aquarium heaters are easy to install and take up relatively little space in your fish tank.
  • Undergravel heaters are heating cables that you bury beneath the gravel of the tank. They often take the form of a cord with a small electric pad. You should consider these heaters if you have a lot of living plants in your fish tank.
  • Under tank heaters are similar to undergravel heaters in that they are a heating pad with a cord attachment. However, these aquarium heaters are placed under the entire fish tank instead of under the gravel in the water. The benefit to these is that the heater is easy to access for maintenance and is relatively easy to install.
  • Filter heaters are heaters that come with an aquarium filtration system. These can often be the best aquarium heaters to buy because the heater is efficient and comprehensive.

>> How much do you need to heat the tank?

When thinking about how to buy an aquarium heater, you will need to know how much power you need to heat the tank. First, find the difference between the average temperature of the room your tank occupies and the temperature of the water your fish need. Then, consult the chart below to find the necessary power level of your prospective aquarium heater. Generally speaking, you will want to round up when it comes to watts, and larger sizes of aquarium heaters generally provide more power.

Tank size

0-9 °F Difference

9-18 °F difference

Over 18 °F difference

5 gallons 25 watts 50 watts 75 watts
10 gallons 50 watts 75 watts 75 watts
20 gallons 50 watts 75 watts 150 watts
25 gallons 75 watts 100 watts 200 watts
40 gallons 100 watts 150 watts 300 watts
50 gallons 150 watts 200 watts 400 watts
65 gallons 200 watts 250 watts 500 watts
75 gallons 250 watts 300 watts 600 watts

If your fish tank is especially large, you might want to consider buying two heaters - one for each end of the tank.

>> Consider mini-heaters

aquarium heater sizes

Knowing how to choose an aquarium heater may include examining 7-15 watt mini heaters for your small fish bowl or betta fish tank. These heaters are also sold in semi-submersible and submersible types. Due to area constraints, small tanks sometimes require more care and attention to maintain a fresh, healthy environment for the fish. With a mini aquarium heater from any one of the aquarium heater brands, you can reduce some of the need for constantly replenishing the water in a small fish tank.

>> Consider aquarium heater features

One feature some of the top rated aquarium heaters have is that you can set them to heat the water to a certain temperature. This gives you more control, which can be good if you have fish that thrive in especially warm or cool water. Other heaters come with a pre-set water temperature. The heater will turn on when the water goes below the set temperature. Keeping the water especially warm can also reduce fish parasites and harmful organisms in the tank. Another type of water heater will automatically shut off if it's not submerged in water. This can be good when you have to clean your tank. Some aquarium heater brands make products that are constructed with shatter resistant materials.

>> Consider how the heater will look in the tank

Finding an aquarium heater that looks good in your tank can be important when you think about how to choose an aquarium heater. Aquariums are fundamentally about viewing the fish, and you will likely want a heater that lets you have a good view of the tank's interior. Consider how your heater will interact with the other elements in your tank. Generally speaking, fish-related pet supplies should provide you with a good view of your fishes.

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Aquarium Heaters Best Sellers

Tetra Submersible Aquarium Heater, 50-Watts

Tetra Submersible Aquarium Heater, 100-Watts

Hydro USA Mini Aquarium Heater in Black

12 in. 300 Watt Heater for 75/125 gal. Aquarium

Elive Ready Set Aquarium Heater 150 Watt 01022
$10.77 $13.23 $15.51 $37.99 $25.89
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